It’s hard to believe that a little more than two years ago, Sam Worthington was a virtual unknown in Hollywood. Although the actor established a comfortable career for himself in his native Australia, until “Avatar” and “Clash of the Titans” came out, he was best known for being the guy that James Cameron entrusted to star in his $400 million vanity project, and everyone consequently wanted to work with. Since then, he’s become a Hollywood mainstay, jumping from blockbusters to independent projects, and remaining one of the most in-demand actors in the industry. And this week, he stars in “Man on a Ledge,” a film in which he plays a desperate, disgraced cop who steps out onto a precipice 220 feet in the air in order to let the world know how egregiously he was wronged.

It’s hard to believe that a little more than two years ago, Sam Worthington was a virtual unknown in Hollywood. Although the actor established a comfortable career for himself in his native Australia, until “Avatar” and “Clash of the Titans” came out, he was best known for being the guy that James Cameron entrusted to star in his $400 million vanity project, and everyone consequently wanted to work with. Since then, he’s become a Hollywood mainstay, jumping from blockbusters to independent projects, and remaining one of the most in-demand actors in the industry. And this week, he stars in “Man on a Ledge,” a film in which he plays a desperate, disgraced cop who steps out onto a precipice 220 feet in the air in order to let the world know how egregiously he was wronged.

The Playlist spoke with Worthington in Los Angeles about his role in the film, including what cinematic predecessors inspired him as he took to the film’s dangerous stunts. Additionally, he offered some specifics about his upcoming project, “Thunder Run,” revealed what criteria he looks for when choosing roles, and reflected on the evolution of his career since “Avatar.”

Did you take any cues from Harold Lloyd for this?
From him hanging on the clock face? (laughs) No, mate. What I watched was I watched an old movie called “The 14th Floor” or something like that, and there was bits where the guy was extremely nervous in it, and I was extremely nervous getting out there, but it’s an act, it starts off being an act, and he’s cool because the plan’s going according to order. I felt the character of Nick at the start should be quite cool out there, but then as his plan starts to unravel, when they start discovering who he is, that’s when it gets more frenetic, that’s when it gets more desperate. So I kind of reversed what they did on “The 14th Floor,” where he’s desperate and then he gets cooler.

Does the story give you enough to do that you don’t have to make this guy stuck in one location interesting?
I think it does, but then it cuts away. [Director] Asgar Leth and the boys are pretty good at pacing; we’re under no illusions – this is a popcorn movie, it’s a fast, frenetic action movie that in the middle of awards season is kind of refreshing. And I think that’s what they’ve done. Whenever they’ve kind of felt we’re dropping the ball, they cut to Jamie Bell, and whenever they thought that’s getting a bit tedious, it’s come back. And that’s what a good director and editor does to keep people amused and get their 16 bucks worth.

Do you need to come up with a back story that justifies the level of cleverness of the character?
Well, if you look at it, the way they rob the place is very kind of low-tech. The plan itself is very low-tech. There’s moments like stopping a crowd with a bunch of money. And that’s what I kind of liked about it – I thought it wasn’t like a high-octane, “Ocean’s Eleven” type of movie. It was the lowbrow version of that, and I kind of liked that. That to me is what made me laugh.

On the other hand, you’ve recently talked about doing “Thunder Run,” which you describe as “Avatar meets TRON.”
I think the guys that are working on it did 'TRON,' and the guys that are working on it did 'Avatar,' so they’re putting both guys together; I think that’s the plan. When I met them and they showed me the kind of screening that they’ve got, and the movie’s so big that you’ve got all of these tanks, that to reset all of these tanks would cost you hundreds of millions of dollars and time would be ridiculous. So the way they’re planning on doing it is a very unique way, and it’s experimental and it seems to be working in the screening they showed me, and it’s only going to improve. So I just wanted to be a part of something that could be quite cutting edge if it works. I like being involved in something like that.

Are you playing a real person?
I’m playing a real person, but however they take my real performance and put it in is going to be different. It’s a bit like the next level of the volume thing, or their rendition of the volume, it seems.

But you’re not being transformed into a Na’vi-like character, right?
No, it will look like 'TRON,' with the young Jeff Bridges. It’s the next, upper-upper level of that, because that’s what they were starting with there, and there were glitches in that or things that didn’t sort of work in that. So they’ve gone back to the drawing board and they’ve come back with another thing with someone else, and they’re going out. It should work, because the thing they showed me looked spectacular.

How much of a plan do you have for your career in terms of taking on bigger, more commercial projects, and maybe smaller ones that are more of a creative challenge?
I don’t do it that way – I don’t kind of plan it. I just choose a movie that I would go and see, and work with people that I would like. [Producer] Lorenzo [Di Bonaventura], I’ve known for years and I’ve liked all of his movies. If you look at the vast range, not only from “Red” and “Transformers” but all of the way back when he was head of studio and putting together things like “The Matrix,” that guy makes movies for an audience. As he said to me when you go in his office, “Look at the movies and tell me they’re not in your top ten.” They make big box office, that’s what he does – he realizes an audience pays money to go and see them – and I said that’s what I like. That’s what the job is, to entertain these people who give their hard-earned cash to go with their family on a Friday night and get lost in a movie for 90 minutes. Working with guys like that, that’s the plan, because they understand there’s an audience involved, and we want to entertain them.

Do you have to focus on what the audience wants more than what you might want as an actor?
I put myself in their position and go, would I go see this movie? Would I pay 16 bucks if that was Colin Farrell standing on the ledge? Why not? Probably, if it’s exciting enough, or if there’s something dynamic about it in the trailer. That’s how I pick them; that’s my only barometer I’ve got. You can’t second guess everything all of the time, and you can’t do it because you go, "Oh, all of the critics are going to love this, or awards are going to love this." I kind of pick it and go, "Would I want to see it?" That’s how I do it.

Do you ever choose movies according to the challenge they present, or the novelty of their experience in your career?
Not really. It’s more when you’re reading the story, you’re not thinking, “Man, if I do this, I’m going to be 220 feet in the air on a ledge.” As my mate said, “You’re a dickhead – it’s called ‘Man on a Ledge,’ where did you think you were going to be?” But I’m reading it going, would I pay money to see this movie? Is it interesting? Is there stuff in it that makes me laugh, or is there stuff in there that makes me go, “Oh, that’s interesting,” or “That’s exciting.”